Suspended ignition arch



Aug. 3 1926 D. H. coUcH SUSPENDED IGNITION ARCH Fld DSO. 14, 1922 Patented Aug. 3, 1926.

vDevin) rtg couon, or WARWICK, nnonn IsLANn.v

SUSPENDED IGNITION ARCH.

This invention relates especially to arches over extended furnaces generally known as Dutch ovens. called ignition or cornbustion7 arches and function as heat reiiectors which improve combustion by creating a hotter zone near where the fuel is being burned. This causes more rapid and complete ,combustion than would be the case if the fire were directly 10 exposed to` the cold boiler surfaces which absorb so much heat by radiation that the furnace is robbed of its heat so rapidly that it cannot generatey heat fast enough to keep the fuel properly ignited until combustion is completed. In other words such an arch is provided to help form a hot refractory lfurnace to assist in the complete combustion of the fuel being used.

The principal objects of my invention are as follows: First, to provide a type of suspended'ignition' or combustion'arch which will have a suificientamount of refractoryA .material to give the necessary aid to combustion of the fuel being used second, to

provide a type ofsuspended ignitiongarch which willl be durableand dependable and one which will not have to be immediately takenout of service if parts of the refractory materialjfall out, as is the case with suspended arches now on the market; third,

to provide an arch which will act, not only as a refractory heat reflector, but one which,

in the case of steam boilers, will add greatly to the steam making capacity of the boiler by providing -additional heating surface so arranged as to absorb avery large amount of heat from the furnace, much of which heat is usually wasted thru the present-types of suspended ignition arches. l

Other objects will appear in the specifications and claims appended thereto.

These objects are attained in the case 4of furnaces for steam boilers by making the supporting members of the arch of steel .or

5 metallic tubes, the lower ends of which are expanded into or otherwise securely attached to a header. 'This header communicates by means of one or more pipe connections to the water space of the boiler.

0 ends of said tube supporting members cornrrunicatel with the boiler steam or water drums or headers, below the water line, but

at a `higher. elevation than the connection just described -at the lower endsof these E' tubes. This makes it possible for some of the boiler water to circulate thru these tubes Such arches are usuallyA The upper Application led December 14, 1922. Serial No. 606,900.

and vprevent themY from becoming overheated. Around these supporting tubes refractory tile, preferably taking the form of a C and usually known as C tile,` is placed to form the refractory portion of the arch. Above the zone which it is desired to keep highly heated, tile taking the form of a T and generally known as T tile may be used on the outside only of the supporting tubes. This allows the tubes to absorb more heat from the furnace by convection or in some cases both by convection and by radiation than would be possible if C tile only were used. Other forms of tile answering the psame purpose may be used or the refractory material may be applied in a plastic form andf allowed to harden, the essence of the invention being the use of tubes or hollow members thru which water, or in certain cases, other liquid circulates by convection oris circulated'by a pump or other means as the supporting members of the arch and refractory material lsurrounding or resting on said supporting members to form the necessary refractory portion of the arch.

The type of boiler to which this arch is to be applied will determine whether a top. header will be required to receive the top ends ofl thesupporting 'tubes or whether these tubes may be attached directly to or expanded into the steam drums, headers or other heating surface of the boiler.Y In the case of Sterling type boilers, the top ends of the tubes may be expanded directly into the front steam drum, while in the case of the Bigelow-Hornsby type boiler a top header with connections at intervals to the drums will be necessary.

The accompanying drawing shows the ap.-

plication of this invention to a SterlingI boiler, but many other typesfof boilers may be equipped with this arch with slightly different details in the means of top and bottom connections to the boiler. Also in some cases it may be found that natural convection currents in the circulating liquid are not sufficient to give the necessary circulation, lin which ycases a pump or equivalent device may be used in series with the arch arch may be used with'stills or other liquid heating vessels' with practically the same `type of connections as that described and `illustratediin the case of steam'boile'rs but `in cases where the pressure of the 'circulatlng liquid: is low, hollow castings or otherl 105.. to produce the required circulation. This forms of hollow arch supporting members may be used instead of tubes.

This arch may also-be used with some types of industrial furnaces, not used in connection with liquid .heating vessels, in which cases water or other suitable liquid may be pumped through or caused by other ing the cast iron protection and tile support for'the bottom of the headers, Fig. 4 is a transversesection at the line 4--4 of a few of the supporting tubes 2, T tile 5, and T irons 40, and Fig.5 is a transverse section' at the line 5-5 of some of the supporting tubes 2, C tile 4 and insulating covering 48.

Similar numerals refer to similar parts throughout the several views.

Referring tothe Figures, 2 represents the supporting tubes of the arch, 3 is the connecting header Aat the lower ends of the tubes 2 into which these tubes are expanded or otherwise suitably attached, 4 is the C tile or refractory portion preferably entirely surrounding the tubes where the hottest zone is required. 5 is preferably a T tile uppenrefractory portion where a high "temperature is not required and it is not necessary therefore to entirely surround the tubes with refractory tile, 6 is the con-l nectmg pipe permitting the circulation of water from the mud drum 9 thru the header 3 and tubes 2 to the front steam druml 10. Pipe 6 is connected to the header and mud drum 9 by the Ts 7 and 8, each of which has one end blanked by -a removable ange to facilitate cleaning. 11 is a blow down valve at the end of header 3 to permit of blowing the water and sediment out of header 3 and tubes 2. Valve 11 is connected to the header 3 by the flanges 12 and 14 and the nipple 13. 15 is a tube or tubes connected between the top of header 3 and steam ldrum 10 in order to readily convey to drum 10 any steam whichv might be generated in the header.l 3 and become trapped above the inlets to tubes 2.

The boiler consists of the mud drum 9, the steam drumsv 10, 16 and 17 and the'tube banks 18, 19, 20, 21, 22 and 23 housed and protected by the setting walls 24, 25 and 26 which rest on the Hoor 27. The fuel is burned on the Stoker or grate or 1n the burner or other apparatus 28 and the products of combustion pass up and down among the tube banks 18, 21, 19 and 2O being directed in their course by the batiies 29, 3(1),v 31 and 32 and are finally discharged past the damper 33 and thru the outlet 34 to the breaching not shown.

The arch is supported at the upper end by the tubes 2 being expanded into or otherwise suitably connected to the steam drum 10. The header 3 is hung from the I beam or other support 35 by the hangers 36. These hangers 36 are preferably attached to the header 3 by lugs, not shown, riveted or welded onto the header 3 or att-ached by other suitable means. y

The C tile 4 surround and are supported by the tubes 2, while the T tile 5 rest on the brackets 37 which are attached to the steel channel 38 by the bolts 39. Brackets 37 therefore support the weight oi' the T tile 5, but these tile 5 are heldin position against theotubes 2 by the angle irons or l T irons 40 which are held in place `at the lower end by a projection which rests against the inside top surface of the channel 38 and are held in place at the top end by hook bolts 41 which hook around the i -heat by the insulating covering 48 and this construction may also be employed on the outside of the T tile 5 if desired.

' Header` 3 is protected .from the heat of the furnace by a cast iron protecting sheath 42 held in place by the straps 43, Fig. 3. 1lhe lower side of these protecting pieces 42 has a T- projection onto which are slipped refractory protecting tile 44, the object of which is to further protect the header 3 and the joint between the C tile 4 and the cast iron protecting pieces 42. Access for expanding, cleaning or removing tubes 2 is provided by a handhole opposite each tube 2. These handholes are closed by handhole' plates 45 which are held in place by the saddle or cap 46 and the nut 47 It is understood that the invention is not limited to the specific embodiment shown andl that various deviations may be made therefrom without departing from the spirit and scope of the appended claims.

What 1 claim as new and desire to secure by Letters Patent is:

1. A steam boiler having a bank of vern tically extending water tubes, upper and lower drums connected to the ends of said water tubes, a furnace chamber in front of and beneath said bank of tubes, a baffle to direct the 'gases from said furnace along said water tubes to the. upper ends thereof adjacent said upper drum, a row of combustion arch tubes extending substantially horizontally over the lower part of said furnace and then substantially upwardly, the tubes of` said row being connected at their upper ends to said upper drum and at ,their lower ends to a header, connections between said header and said lower dru tile surrounding the substantially` horizontal portions of said arch tubes and arranged to close the spaces therebetween, and tile cover; ing the spaces between the substantially Vertical portions of said arch tubes to form a front furnace wall and arranged to expose said substantially vertical portions' to the gases rising along said bank of water tubes.

2.- A steam boiler having a bank of vertically extending water tubes, upper and lower drums connected 'to the ends of said water tubes, a furnace chamber in front of and beneath said bank of tubes, a baiie to direct the gases from said furnace along said water tubes to the upper ends thereof adjacent said upper drum, a row of com bustion arch tubes extending substantially horizontally over the lower part of said furnace and then substantially upwardly, the tubes of said row being connected at their upper ends to said upper drum and at their lower ends to a header, connections between said header and said'lower drum, tile surroundin the substantially horizontal portions o said arch tubes and arranged to close the spaces therebetween, and tile covering the spaces between the substantially vertical portionsof said arch tubes to form a front furnace wall and arranged'to expose said substantially vertical portions to the gases rising along said bank of water tubes, said substantially vertical portions having an angle to said bank of water vtubes to form an upwardly progressively contracting combustion space.

In testimony whereof I have affixed my' signature. ,K

. DAVID H. COUCH. 

